PDL::IO::HDF (4) documentation

NAME

PDL::IO::HDF - A PDL interface to the HDF4 library.

SYNOPSIS

use PDL;
use PDL::IO::HDF;
# Open file 'foo.hdf' with all hdf interface:
my $HDF = PDL::IO::HDF->new("foo.hdf");
# You can call functions from either the SD or VS interfaces:
$HDF->{SD}->SDget("Foo_data");
$HDF->{VS}->VSgetnames();
# To close the file:
$HDF->close();

DESCRIPTION

This library provides functions to manipulate HDF files with the SD, VS, and V HDF interfaces.

For more information on HDF, see http://hdf.ncsa.uiuc.edu/

The 'new' function of this package uses the 'new' functions for the individual HDF interfaces. This allows you to use all of the interfaces at one time (if you don't mind the extended syntax).

Actually using the HDF files comes down to using one of the particular interfaces, for that see the docs on those modules.

CONSTANTS

These constants are now implented using the perl 'use constant' pragma.

Previously, they were just scalars that were changeable (which is a no-no).

See constant(1) for more info on how to use these in your code.

Access Modes

DFACC_READ

Open the file in read-only mode.

DFACC_WRITE

Open the file in write-only mode.

DFACC_CREATE

Clobber the file (create it if it doesn't exist, and then open with RW mode).

DFACC_ALL

Open the file in read-write mode.

DFACC_RDONLY

Same as DFACC_READ

DFACC_RDWR

Open the file in read-write mode.

VS Interface Interlacing Modes

FULL_INTERLACE

NO_INTERLACE

HDF4 Data Type Codes:

DFNT_UCHAR

HDF's unsigned char ~= PDL's byte

DFNT_CHAR

HDF's char ~= PDL's byte

DFNT_FLOAT32

HDF's 32-bit float ~= PDL's float

DFNT_FLOAT64

HDF's 64-bit float ~= PDL's double

DFNT_INT8

HDF's 8-bit integer ~= PDL's byte

DFNT_UINT8

HDF's 8-bit unsigned integer ~= PDL's byte

DFNT_INT16

HDF's 16-bit integer ~= PDL's short

DFNT_UINT16

HDF's 16-bit unsigned integer ~= PDL's ushort

DFNT_INT32

HDF's 32-bit integer ~= PDL's long

DFNT_INT64

HDF's 32-bit integer ~= PDL's long

Misc. HDF Library Constants:

MAX_NC_NAME

This is the max name length for SDS variables, attribtues, and just about anything else.